رايكم ايه:He is an English teacher.

[الاستاذ خالد زلط]

Sorry, there is no differentiation of meaning by stress in that way.
"Scottish teachers are conservative, but English teachers are more liberal." Stress relates to ethnicity, not subject taught.
"Physics teachers are conservative, but English teachers are more liberal." Stress relates to subject taught, not ethnicity.
In normal conversation I would expect no difference whatsoever in the enunciation of "English teacher" as meaning ethnic English teacher and teacher of English. Those meanings depend on context, not on stress.
جزاك الله خيرا يا مستر علي افادتنا.